Illumination device

Abstract

An illumination device includes an image element configured to convert light incident thereon to image light and to output the image light, a first light path extending to pass through the image element, and a second light path extending without passing through the image element. The first light path and the second light path are configured to project lights passing therethrough, respectively, on an object existing outside the illumination device.

What is claimed is: 
     
       1. An illumination device, comprising:
 an image element configured to convert light incident thereon to image light and to output the image light; 
 a first light path that passes through the image element; 
 a second light path that does not pass through the image element; and 
 a single light source configured to generate light passing along the first light path and along the second light path, 
 wherein the first light path and the second light path are configured to project light passing therealong, respectively, on an object located outside the illumination device, 
 the image element comprises a substantially planar element, and the first light path and the second light path respectively extend through two separate regions on a plane including the image element, and 
 the first light path and the second light path are two split light paths, extending directions of the first and second light paths are substantially identical with each other, 
 the illumination device further comprises a light shielding member configured to isolate at least a portion of the first light path from the second light path, wherein the light shielding member surrounds a peripheral portion of the image element, and 
 the light shielding member is provided between the first light path and the second light path and does not transmit light. 
 
     
     
       2. The illumination device of  claim 1 , further comprising:
 a projection lens configured to project the light passing along the first light path and the second light path, respectively, on the object, 
 wherein the first light path includes a light path extending toward the projection lens via the image element, and 
 the second light path includes a light path extending toward the projection lens without passing through the image element. 
 
     
     
       3. The illumination device of  claim 2 , wherein, when viewed in the extending direction of the first light path, the first light path is surrounded by the second light path in at least a portion thereof along the extending direction. 
     
     
       4. The illumination device of  claim 2 , wherein at least a portion of the first light path is provided adjacent to the second light path without being isolated from the second light path. 
     
     
       5. The illumination device of  claim 2 , wherein the image element includes a light-transmission-type image element configured to convert the light transmitting therethrough to the image light. 
     
     
       6. The illumination device of  claim 5 , wherein the first light path and the second light path are two light paths split on a plane including the two separate regions, one of the regions is an image forming region where the image element is provided and the other of the regions is a light transmitting region,
 the first light path is for light passing through the image forming region to be incident on the projection lens, and 
 the second light path is for light passing through the light transmitting region to be incident on the projection lens. 
 
     
     
       7. The illumination device of  claim 6 , further comprising:
 a planar substrate including a light transmitting member, and 
 wherein the image element extends into an opening defined at a center of the light transmitting member, and 
 wherein the image forming region and the light transmitting region are provided in the planar substrate. 
 
     
     
       8. The illumination device of  claim 6 , further comprising a frame-shaped holding member,
 wherein the frame-shaped holding member holds the image element by using an opening defined at a center of the frame-shaped holding member, 
 wherein additional openings are provided inside of the frame-shaped holding member and the light transmitting region is defined by the frame-shaped holding member and the additional openings. 
 
     
     
       9. The illumination device of  claim 5 , wherein the image element includes a transmission-type liquid crystal panel. 
     
     
       10. The illumination device of  claim 9 , further comprising:
 a polarizing element that includes a light transmitting region and a polarization control region where a polarization control element for polarizing light moving toward the image element or light emitted from the image element is provided. 
 
     
     
       11. The illumination device of  claim 10 , wherein the polarizing element further includes a substrate in which the polarization control region and the light transmitting region are provided. 
     
     
       12. The illumination device of  claim 2 , wherein the image element includes a light-reflection-type image element configured to reflect the light incident on the image element as the image light. 
     
     
       13. The illumination device of  claim 12 , wherein the first light path and the second light path are two light paths split on a plane including the two separate regions, one of the regions is an image forming region where the image element is provided and the other of the regions is a light reflecting region,
 the first light path is for light that is reflected in the image forming region to be incident on the projection lens, and 
 the second light path is for light that is reflected in the light reflecting region to be incident on the projection lens. 
 
     
     
       14. The illumination device of  claim 13 , further comprising:
 a substrate, and 
 wherein the image forming region and the light reflecting region are provided in the substrate. 
 
     
     
       15. The illumination device of  claim 13 , wherein the image element includes a reflection-type liquid crystal panel. 
     
     
       16. The illumination device of  claim 12 , wherein the image element includes a micro mirror array. 
     
     
       17. The illumination device according to  claim 1 , the light shielding member comprising a mask. 
     
     
       18. The illumination device according to  claim 1 , the light shielding member comprising a planar member. 
     
     
       19. The illumination device according to  claim 18 , the light shielding member being provided in a plane that is substantially parallel to the plane including the image element.